The invention relates to a back rest for lifting apparatus useful for insertion in a bathtub, comprising a foot part capable of being mounted on a lift platform of the lifting apparatus and a slab, pivotably mounted on said foot part and forming a back part, together with an adjustment means with which to adjust the angle of inclination of the slab.
A back rest of this kind is known from U.S. Pat. No. 4,932,087. The adjustment means consists of a locking hinge arranged coaxially to the swivel axle. The angle of inclination of the slab can be adjusted very finely, but it is necessary to move the slab parallel to the direction of the swivel axle prior to adjusting the angle of inclination, in order to release the snap-in lock. Once the angle of inclination has been adjusted, the lock snaps in automatically thanks to a built-in spring, at least as long as there is no load on the back part. Since lifting apparatuses of this kind are frequently used by handicapped persons who do not have perfect control over their body movements, it is often problematic for the user to adjust the angle of inclination himself, firstly because the back part is difficult to move into the swivelling position when there is a load on it, and secondly because any supporting function is lost in said swivelling position, so that, under load, the back part jerks backwards. Even for a helper, it is often not easy to move the back part from a flatter angle of inclination to a steep angle when the user is applying a load to it.